The invention relates to a measuring device for determining the channel-quality feedback quality from mobile stations within mobile radio communications systems and a method for determining the channel-quality feedback quality of mobile stations within mobile radio communications systems.
Mobile stations in mobile radio systems conventionally report to the base station connected with the mobile station regarding the quality of the communications channel in a channel-quality feedback message, referred to below as a channel-quality feedback. A maximization of the transmission rate attainable with a given spectrum is achieved, for example, by adapting the modulation method. In this manner, the base station can guarantee an optimum transmission. Conventionally, the signal-noise ratio of received, known data is determined for this purpose by the mobile station. A channel-quality feedback (channel-quality feedback) is generated from this and transmitted back to the base station.
For example, the U.S. patent application U.S. 2007/0064632 A1 discloses a mobile-radio system, in which mobile stations transmit a channel-quality feedback to the base station. On the basis of the channel-quality feedback of the mobile station, the base station adjusts the modulation. In this manner, an increase in the attainable transmission rate is possible.
In future mobile-radio systems, MIMO (Multiple In Multiple Out; multiplex input-multiplex output) will be used, this means that several transmission antennas and several reception antennas are used in each case. To achieve a further increase in capacity, different data can be transmitted via the several transmission antennas. The signal-noise ratio of the several individual communications channels is now no longer sufficient to provide a reliable evaluation of the channel quality.